Sterling silver.



UNITED STATES PATENT @FJFIQE.

EDWARD D. GLEASON, OF NEW YORK, N. Y., ASSIGNOR T0 FRANK JOHN BOESLER,OF BROOKLYN, NEW YORK.

STERLING SILVER.

No Drawing.

To all whom it may concern Be it known that I, EDWARD D. GLEAsoN, ofBrooklyn, in the county of Kings, city and State of New York, haveinvented a certain new and useful Improvement in Sterling Silver,whereof the following is a specification.

The term sterling silver is limited by statute to a silver alloycontaining at least .925 of silver, and the balance of .075 usuallyconsists of copper.

It is an object of my invention to provide silver alloys Within thestatutory degree of fineness aforesaid, of dilferent degrees ofhardness, and particularly to provide such an alloy of greater hardnessthan may be produced by alloying silver with copper alone.

A further object of my invention is to provide such alloys which may bereadily cast, in sand or other suitable molds, withoutthe honey combdefects which are usually formed in ordinary sterling silver castings bythe occlusion of gas.

I attain the objects aforesaid by alloying the pure silver with coppercontaining more or less boron in accordancewith the degree of ofhardness of the alloy desired. In carrying out my process I prefer tofirst incorporate the boron in the copper, preferably by subjecting thecopper to the action of boron fluorid while the copper is molten, whichresults in the deposit of bo-ron in the graphitoidal st-atein the copperwhen the latter cools. Such boron copper, when alloyed with silver inthe proportions herein contemplated, renders the molten alloy free fromoccluded gases, so that castings made therefrom are homogeneous and freefrom the defects aforesaid. However, it is to be noted that such aneffect is not produced by Specification of Letters Patent.

Patented Oct. 14L, ISM-3.

Application filed December 31, 1912. Serial No. 739,455.

employing boron alone with silver, but is only attained when the boronis mixed with the silver in association with other metal.

I note that, within the proportions herein contemplated, silver alloysmay be made of such hardness as to fracture like low carbon i teel, andincapable of being rolled to sheet orm.

My improved alloy is advantageous in that what is called pierced work,to wit, sheet metal articles having designs manifested by perforations,may be made of thinner sheets, with the same degree of rigidity, as ifmade of ordinary sterling silver, and that castings made in accordancewith my invention, in ordinary molds, are commercially perfect and onlyrequire to be buffed or otherwise finished for commerce. Of course, inview of the greater hardness of alloys made in accordance with myinvention, articles made therefrom either in sheet or cast form are moredurable than ordinary sterling silver articles because of the resistanceof my alloy to abrasion.

I do not desire to limit myself to the precise procedure hereinbeforedescribed as it is obvious that various modifications may be madetherein without departing from the scope of my invention as defined inthe following claim.

I claim Sterling silver containing from .900 to .925 silver, alloyedwith from .75 to .100 copper and boron.

In testimony whereof, I have hereunto signed my name at Philadelphia,Pennsylvania, this thirtieth day of December, 1912.

' EDWARD D. GLEASON.

Witnesses:

ANNA IsRAELITz, ETHEL M. IMSOHWEILER.

